Most packages in which food products are sold are provided with lids hermetically sealed in place so as to prolong the shelf life of the package prior to sale; however, after having been sold and opened, the lid is sufficiently damaged and/or distorted so that it cannot be reapplied readily and/or sufficiently securely so as to exclude the ambient atmosphere. Hence, the contents of the package will spoil in a relatively short time. Furthermore, generally the lid is comprised of a relatively thin material so that when placed in storage, it will not support other items on top of it and when such items are placed on top, the lid is deflected downwardly, thus producing gaps which admit the ambient atmosphere into the container. It is a purpose of this invention to provide a container wherein the lid is initially attached by heat-sealing or its equivalent and also with mechanical means which may be disengaged to release the lid when the heat-sealed portion is broken to permit the lid to be removed and thereafter restored after partially using up the contents of the receptacle with a sufficient degree of tightness as to exclude the ambient atmosphere and to provide a lid comprised of relatively thin material with a relatively thick cover board reinforcement which provides means for obtaining an undercut engagement for package resealing without using heavy material for the lid.